Traffic-related particle emissions that result not from exhaust gases but rather from abrasion of brakes, tires, clutches, roadway paving etc., and also from re-whirling of road dust, contribute considerably to air pollution. It is expected that exhaust-gas particle emissions will decrease by reason of strict limits, but the other traffic-related particle emissions will increase by reason of greater traffic volume, and could become a focal point of future regulations. Data from the Deutsches Umweltbundesamt [German Federal Environment Agency] give cause to expect that exhaust-gas particle emissions in the year 2020 will make up about 18% of all traffic-related fine-dust emissions, in which connection the term “fine dust” denotes the particles having aerodynamic diameters of less than 10 μm. The remaining 82% are emissions caused not by exhaust gas but rather by wear. This shows the increasing importance of the particle emissions not caused by exhaust gas.
For the purpose of reducing brake-dust emissions especially, techniques are known such as, for example, shielding arrangements, blowers and dust collectors. For instance, DE 20 2007 000 246 U1 discloses a brake-dust collector in which a fan generates a stream of air which transports brake dust that has arisen to a filter element. The filter element may be of electrostatic construction, in order to assist it by electrostatic accretion of dust particles. The fan blades may be constituted by rim spokes.
DE 10 329 961 A1 discloses an integrated fine-dust suction apparatus for vehicles, with which fine dusts can be filtered out of the ambient air and collected for scientific investigations. The fine dusts can also be analyzed during the collecting process with an aerosol spectrometer by way of dust-measuring instrument, in which case the measured data can be relayed by radio.
Motor vehicles have also already been proposed with which the ambient air is to be cleansed of fine dusts during a run.
For instance, DE 20 2006 019 335 U1 discloses a fine-dust suction apparatus for vehicles, with which the fresh air supplied to the passenger compartment of the vehicle can be cleansed of fine dusts, but with which the fine-dust content in the ambient air can also be reduced, in order to comply with legally prescribed fine-dust limits.
DE 20 2006 004 522 U1 discloses a fine-dust filter operating with electrical or magnetic separation. The fine-dust filter is arranged between the air-inlet grille and the radiator of a vehicle in order to cleanse the ambient air, flowing through there, of fine dusts, including fine dusts which have been emitted or whirled up by other vehicles.
DE 20 2005 005 673 U1 discloses an outside-air filter for motor vehicles, mounted beneath a fender, for general reduction of air pollution.
Systems of such a type could only reduce fine dust in the environment effectively if they were installed in a very large number of vehicles, and the expenditure for cleaning the many filters and for disposing of the collected dusts would be extreme, especially since comparatively coarse dusts, which are not really harmful, would also be collected, and the filters would quickly become full.
Motor vehicles have also already been proposed that make it possible to collect more selectively the dusts emitted or whirled up by a motor vehicle itself.
For instance, KR 101 511 663 B1 discloses a motor vehicle with a duct extending within the wheel housing, which during a run takes up air which is laden with dust that has been whirled up, and conveys it through a dust filter.
JP 2008 302 803 A discloses a dust collector for dust whirled up by a motor vehicle, wherein an air-inlet opening is situated downstream of a vehicle wheel, from which air laden with dust is conveyed by a fan into a dust-collecting bag via a duct.
CN 2 052 369 U discloses a motor vehicle having a dust-trap, arranged downstream of a vehicle wheel, with an air-inlet opening situated underneath, into which air which is laden with dust that has been detached from the wheel enters automatically during a run. In the event of rain or humidity, the air-inlet opening is capable of being closed with a flap. At its upper end the dust-trap has an air outlet which is connected to a passive dust collector such as a vortex separator.
Advantageously, a motor vehicle equipped with the dust collector disclosed in this document collects the dusts emitted or whirled up by the motor vehicle itself—that is to say, dusts resulting from abrasion of brakes, tires, clutches, roadway paving etc. and also from re-whirling of road dust—particularly selectively.
This object is achieved by a motor vehicle having the features disclosed herein.